Slotter head



Jan. 11,1938. "r. s. FlTCHETT SLOTTER HEAD Filed Feb. 13, 1936 Patented Jan. 11 1938 lTE STATES PATENT OFFICE SLOTTER HEAD Application February 13, 1936, Serial No. 63,694

7 Claims.

The invention relates to the cutting, or more particularly to the slotting of paper or similar material and has particular reference to the rotary, or oscillating type of cutter or slotter heads which in the development of the present invention have been applied to the slotting of box partitions of which the cellular or crate partition is an example.

The invention to be described is, however, in its broader conception capable of application to the slitting of box blanks and the like and even to scoring.

In the cutting of paper box partitions or crates and the like the variation in the thickness of the paper, and the consequent necessity for a variation in width of the slots cut in the partition members to provide for the well known interlocking feature has led to the development of the multiple groove female cutter or slotter head. As a large proportion of these partitions are of corrugated board which is generally made in two standard thicknesses, the multiple groove cutters or slotter heads are most commonly two groove female cutters, having their grooves of widths corresponding to these two standard thicknesses of board and located side by side, called double groove slotter heads, and the cooperating male knives are of such thicknesses, respectively as to fit and enter these grooves so that the cooperating male and female cutters are in practice adapted to cut slots of two standard widths to receive paper board of these respective thick- It should be understood in this connection that the male and female slotter heads of this type are mounted on parallel shafts which are positively geared together to run at the same speed or speeds, the male slotter heads being on one shaft and spaced according to the spacing of the partition and the female cutter or grooved slotter heads on the other shaft and similarly spaced. The'male knives fit each in its groove in the corresponding female or grooved slotter head with a considerable degree of nicety giving a shearing cut at each edge, i. e., on each side of the groove, and the edges on each side of each male knife and on each side of each groove of the female or grooved slotter head are sharpened for this purpose.

To cut relatively narrow slots the malecutters of the narrow width are placed on the male heads and the heads are adjusted on their shafts to cooperate with the correspondingly narrow slots of the double groove slotter head or female cutter and to cut the wider slots the narrow male cutters are removed and replaced by the thicker male cutters and. the female cutters or double groove slotter heads are readjusted along their shaft to receive these cutters in the corresponding slots, the spacing being chosen to suit the 5 Work,

To make cellular partitions or crates on any slotter of this general type, it is necessary to place a number of male slotter heads and knives properly spaced on one shaft and an equal number 10 of grooved or female slotter heads similarly spaced on the other shaft. In the prior art machines the dilferent Width grooves being side by side, it is necessary in changing from one width of slot to the other, not only to change the male 15 knives, but to loosen and move along the shaft and respace all the male cutter heads in order that the male cutters may mesh with the grooves in the grooved or female heads. Also, the width of the female cutter heads or their axial length with their two grooves side by side is such as to prevent short, i. e. close spacing of the slots to be cut as the corresponding grooves of the different double grooved heads can not be placed sufiiciently close together, also each double 2 grooved slotter head or two grooved female cutter consists in the existing practice of three knives having four cutting edgesto be sharpened.

The object of the invention is to improve and simplify the present existing slotter construction and operation and to increase its efficiency by decreasing the time requiredto adjust the machine to different work and the cost of maintenance and to reduce the minimum spacing of the slots to be cut. 35

In the improved construction the multiple different width grooves of the female or double grooved slotter head are placed end to end or in substantial alignment circumferentially instead of side by side. The shafts carrying the male and female cutter heads, respectively, being positively geared together to operate together, the male knives are so placed as to enter the corresponding grooves in the female or grooved slotter head, as the shafts revolve or oscillate.

An important advantage of the invention is that one side, i. e., one cutting plane of both the corresponding male and female knives and grooves of all widths is in accordance with the improved construction and operation located in a common radial plane of both shafts for any operative adjustment of the slotter heads so that neither head need' be adjusted along its shaft as the width of the slot is changed providing the spacing of the slots to be cut is not changed.

the preferred form but two cutting edges and the.

number of different widths of groove and male slotter blades is not definitely limited but maybe increased Without increasing the width or axial length of the grooved slotter head.

The accompanying drawing illustrates a single slotting or cutting unit embodying the features of my invention in the preferred form. The manner of driving the slotter shafts, feeding the...

paper board thereto and of spacing and arranging the slotter units on the shafts being matters well known in the art, illustration of which is regarded as unnecessary.

In the drawing:

Figure. 1 is a bottom plan View of a double groove slotter head made in accordance with the invention and assembled on the lower slotter shaft which is shown fragmentarily.

Figure 2 is a similar View of the slotter head parts released from the assembled relation and moved slightly apart in the direction of the axis.

Figure 3 is a front elevation of a single slotter unit, the upper and lower slotter shafts on which a series or gang of these units would ordinarily be mounted being shown fragmentarily.

Figure 4 is a side elevation of the unit looking from the right in Figure 3, the shafts being shown in section.

Referring to the drawing by numerals, each of which is used to indicate the same or similar parts in the different figures, the upper and lower slotter shafts l and 2 are positively geared together as by toothed gears l and 2 secured to the respective shafts and shown fragmentarily in Figure 4, to maintain a uniform angular relation between the shafts in accordance with the practice prevailing in the art. This practice generally provides intermeshing toothed gears of equal size secured to the respective shafts. The existing practice also provides for continuous rotation of the slotter shafts and suitable feeding of the material indicated at 3, in Figures 3 and 4. This is the preferred construction and operation in the present instance.

It is also feasible in place of the above described operation to oscillate the slotter shafts and the slotter heads thereon, changing the time of oscillation to bring either knife into cutting relation with the corresponding groove, and presenting the material by means of a reciprocating feed by which it is withdrawn after each cut, the drive and feed are, however, no part of the present invention, which relates to the slotter unit.

Referring again to the drawing, the upper slotter or cutter shaft the term slotter being generally used in the art to designate machines and cutters intended to perform the operation above indicated, carries secured thereto a suitable number of male or upper slotter heads of which a single one is shown at i and the lower slotter, or cutter shaft 2 carries secured thereto a similar number of female cutter heads or, as they are termed in the art, lower grooved slotter heads of which one is shown at 5, in operative relation to the head 4.

As shown, the upper or male head l is in the form of a split collar having its ends' and 4 slightly spaced and connected by a screw 6 at right angles to the radius at said ends 5', 4". By means of this screw 6 the head t is clamped to the shaft I at the will of the operator or released to be moved along the shaft and reclamped in any desired position of adjustment. The angular relation of the head f to the shaft is maintained constant by means of a key or feather i which extends the entire length of the shaft on which the heads 4 are to be mounted and engages a groove 1 in the inner periphery of the head The axial end surface 8 of the head t is also rabbeted or cut away on one axial end or side, i. e., on the right in Figure 3 beginning at points spaced on each side of the ends 4', 4" and extending around the head from these points, forming a knife seat 9 having a base surface it parallel to the axis and in the form of a circular arc concentric with the axis of the shaft I and a positioning and supporting surface H, in a plane at right angles to said axis. For cooperation with each upper or male head 4 a plurality of knives are provided. In the form shown there are two of these knives indicated by reference characters I? and i i. These are each respectively according to the practice,

of a thickness slightly greater than the thickness of the material to be cut and interlocked, in the manufacture of box partitions.

While the double groove slotter of the invention is particularly adapted to use in the manufacture of crates or interlocking partitions from paper board and/or corrugated board of two standard thicknesses, it may be applied to other uses and the thickness or width of the knives likewise the width of the grooves to be further described may be otherwise determined.

The knives l2 and M are adapted to be supported and secured in the seat 9. As shown they are of substantially arcuate form having the inner periphery of proper radius to fit the base Iii of the seat 9, the outer or cutting edges i5 projecting beyond the outer surface it of the male or upper head 4 which is preferably of short cylindrical form. This surface may cooperate with the corresponding surface I? of the lower head to guide the material and hold it in cutting relation to the knives.

The knife l2 which has its cutting edges i2", 52 spaced by the full thickness of its blade, knife M being similarly constructed, is held in operative position in the seat 9 by means of cap screws 53 which engage tapped holes l9 extending into the male head 5 parallel to the shaft axis from the positioning and supporting surface ii. These screws are passed through holes 263 suitably located in the knife 42 and the knife it is similarly secured by means of'similar bolts not shown entering tapped holes 25 and passing through holes 22 in knife it.

It will be noted that the knives i2 and id as shown are symmetrically located on opposite sides of a diameter drawn between the ends 5, a" of the collarlike head i and that the position of cutter if is indicated in dotted lines meaning that in the preferred arrangement and operation of the slotter but one cutter is in place at a time. It is essential so long as the upper or male head i is to cooperate with the head 5 or one so related to the shaft 2 and having its grooves identically located and of the same di mensions that the knife 52 or M, whichever one is being used, be mounted in its proper relation to the head 4 in orderthat it may enter the corresponding slot in the head 5 or the portion of the slot in said head which is of corresponding width. 'To avoid dislocationor improper meshing, it has been suggested that shafts! and 2 be positively geared together.

, To effect a clean severance of the material at the bottom or end of each slot'cut in the paper, the end of each knife is concave and pointed as shown at 2 3, 2 3 and the two outer peripheral edges of the knives at 12" and i2 are sharpened.

Many of the details above described are capable of wide variation within the skill of the designer.

The lower or grooved slotter head 5 embodies important features of the invention. It is frequently necessary, as already pointed out, to change the width of the slots cut by such a machine to conform to paper board of different thicknesses. For this purpose the double groove slotters now in use have the lower or grooved head provided with two grooves side by side and of widths corresponding respectively to the thickness of these two standard thicknesses of board. Some of the disadvantages of this arrangement have been discussed.

These and other difficulties of the prior art construction have been reduced and overcome by the provision of multiple width grooves arranged end to! end in substantial alignment and preferably in continuity so that the multiple grooved cutting head which in accordance with the requirements of the present practice is a two grooved or double grooved head, has but two cut-- ting edges and two cutting members or knives.

The grooved cutting head 5 is shown most clearly in Figures 1 and 2.

The grooved slotter head 5 in the preferred form shown, it being understood that variations of form and detail are contemplated, consists of two slotter members or knives 25 and 26. These are preferably shown of ring or hollow disk shape, the inner periphery of each at 27 being circular and adapted to fit the lower shaft 2, which is grooved at 29 to receive a key 28. This key enters a suitable key slot in each of the slotter members or knives 25 and 26. These members 25 and 26, Which are of equal diameter are secured together with their outer peripheral circular surfaces I! and their inner peripheral surfaces 2'1 in alignment in the directions of the axis, by means of screws 39 which are spaced along the circumference between the inner and outer peripheries. The slotter head 5 as assembled, in the form shown, is therefore of short cylindrical or flat ring shape, and is mounted on the shaft 2 for adjustment along the shaft, being clamped in adjusted position by means of a clamping screw 32 which is radially placed engaging a threaded hole 3i conveniently located as to the cutting edges preferably as shown. The clamping screw 3i bears directly on the key 28, which serves to maintain the angular relation between the slotter head and shaft in all positions of adjustment of the slotter head along the shaft.

The arrangement of the slotting or cutting edges retains the advantages of the double groove slotter head, and avoids difficulties of the old type having the grooves side by side.

In the preferred form of head shown which is capable of considerable variation within the scope of the invention, the slotter member 26 is provided with a spacer 32. This is shown in the form of a boss surrounding the inner periphery of shaft opening 21, though it is not essentially integral with either slotter member. The peripheral surface 32 of this boss lies below the path of the knives i2 and i4 and the surface 33 is offset so that it lies in two parallel planes providing surfaces 34 and 35 at right angles to the axis, connected by key surface 35 parallel to or in a plane of the axis and extending across the boss in the direction of a diameter. The inner face of the member 25 as to an area 31 surrounding the inner periphery 2? is the complement of the surfaces 33, 36, 3'5, 38 of the boss, said area having flat surfaces 3t, 35 and key surface 36 so that the slotter members 25, 26 fit together in one exact angular relation and one only. The parts may be otherwise keyed, one relatively to the other, in various ways. In the construction shown they are further located by means of dowel pins 38 which extend through slotter member 25 into slotter member 26 parallel to the axis. The members 25 and 25 thus positioned are secured together as described by means of screws 30.

The arrangement of a plurality of slotter head grooves or slots, the term groove being used for convenience to describe either a groove or slot, the closing of the bottom of the slot not being essential, said grooves or slots being of different widths and arranged end to end in substantial alignment in the direction of the circumference of the head so that these grooves can be engaged by male knives similarly arranged on the cooperating male head, the male knives with the exception of one knife being in accordance with the present operation removed or otherwise rendered inoperative for the cutting operation in order to cut slots of a single width, is of primary 1 importance.

In the form shown the slotter member 26 has its peripheral edge 40 which is disposed toward the member 25, located in a flat plane at right angles to the axis, and the surface of member 26 within said edge is shown as undercut at 41 to increase the sharpness and shearing qualities of said edge.

The peripheral cutting edge 42 of slotter member 25 which is disposed toward member 26 is also undercut, as is the edge 46, this feature in both instances being preferred but not essential. The edge G2 in the form shown is in two radial planes both parallel to the plane of edge 48 and substantially at right angles to the shaft axis. The portions of edge 42 indicated by 42 and 42" are both parallel or substantially parallel to the edge 40 to the extent that the cuts at each side of the slots produced by these edges are parallel or sufficiently close to parallel for the purpose in hand. The distance between the plane of edges Q2 and the plane of edge d2", 1. e., the offset, represents the difference between the spacing of edges 46 and 62 and the spacing of edges 40 and 42", and hence the difference between the width of groove 15 and groove 46 between their edges when the parts are assembled and secured by inserting and tightening screws 30, as seen in Figure 1. The offset at 4! between theedges is preferably in line with surface 36'.

For convenience, in producing, maintaining and sharpening, etc., the edges 42' and 42" are connected by an inclined edge portion 47. It is not necessary for all purposes and in accordance with the broader conception of the invention that grooves 45 and 46 be continuous or in exact align ment, but important advantages result from hav ing one edge of the two grooves in exact alignment in a plane at right angles to the axis of rotation as described.

In accordance with the existing practice, the corrugated board'most generally used for box partitions comes in two standard thicknesses and the slotters used for this purpose have been adapted to the cutting of slots of two corresponding widths substantially equal to the thickness of the board. The partitions interlock with other partitions of the same thickness hence the slots are for this purpose made of a width equal to the thickness of the material being cut. To meet the requirements of the practice, the knife !2 may be of an inch in width and it fits rather closely within the groove or slot 55 in which it rolls in the operation of the slotter to cut slots of this width which corresponds to the thickness of the standard material known as B fiute. To cut the wider grooves for the thicker material, the knife I 2 is according to the preferred operation removed and a thicker knife M is secured in the position in which it is shown in dotted lines, Figure 4.

According to present standard, the knife Hi may be inch thick corresponding to A flute board and groove 46 is of corresponding width so that knife l4 fits closely therein. In operation the knife 64 rolls in groove it. In slotting partition strips the slots are cut from one edge half way across the partition. With either knife removed and the other secured in its proper position as shown in each unit, and the proper number of slotter units properly spaced being secured to the two shafts i and 2, the male heads on one shaft and the grooved heads on the other, and the partition strips being presented in proper time with the slotter operation, feeds for this purpose being Well known in the art, the slots will be out of proper depth and width and with the desired spacing.

The positioning of both knives I2 and M, as indicated in Figures 3 and 4, so that the surface 52' of knife 52 and the edge E2 of this knife are in the same plane as are the corresponding surface and edge of knife M when it is in use, serves in connection with the similarly aligned cutting edge or edges Ml of both grooves or slots, &5 and M5, which edge or edges 58 out in the same plane as do the corresponding edges of knives i2 and id to eliminate the necessity for changing the position of either the female or grooved head 5 or the male head :i when the width of the slots to be cut is changed. This improved result or operation is predicated on the fact that without regard to the width of the grooves 45 and 46 and knives l2 and i l, the spacing of the corresponding edges or sides of the slots cut in the paper is determined for all practical purposes by the spacing of the shearing edge Gil of one cutting unit 4, 5 from the corresponding cutting edge Mi of the next unit. This and the spacing of the male knives is changed only when the spacing of the slots cut is to be changed. The ability to change the width of the slot cut in the material in this way without change of adjustment effects a considerable saving of time in operation and a considerable increase in facility with which the machine may be operated by the average workman in a paper box plant.

The placing of the different width grooves of the female head in alignment instead of side by side is also of advantage on account of the reduced axial length of the grooved head 5 in that it provides for a considerably shorter spacing of the slots to be cut and it further cheapens the construction by providing for the use of two female knives or cutter members 25 and 26 with two cutting edges 40 and 42, instead of three female knives and four cutting edges as in the old type having the grooves side by side, though these edges need not in some forms of the invention be continuous as shown.

I have thus described a slotter unit embodying the features of my invention in the preferred form, the description being specific and in detail in order that the manner of constructing, applying, operating and using the invention may be fully understood. However, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined in the claims.

What I claim as new and desire to secure by Letters Patent is:

1. A female slotter head for paper board and the like adapted to be mounted for operative movement about an axis, the head having a plurality of cutting slots, the respective slots being of different widths and each having a shearing edge extending along each of its sides, the shearing edge on one and the same side of two of said slots being located in a single plane at right angles to said axis. I

2. A female slotter head for paper board and the like adapted to be mounted for operative movement about an axis, the head having a plurality of cutting slots, the respective slots being of diiferent widths and each having a shearing edge extending along each of its sides, the shearing edges on one and the same side of two of said slots being located in a single plane at right angles to said axis, and in combination therewith a male slotter head adapted to be mounted for movement about an axis parallel to the axis of the female slotter head and in operative relation thereto, the male head having means for positioning and holding a plurality of male slotting knives, said positioning means being adapted to locate one cutting edge of twoof said supported knives substantially in said plane of the shearing edges of said slots, on said one side and two slotting knives of respective widths to enter said slots, having their edges spaced to cooperate with the edges of said slots and adapted to be secured to said male head in slotting relation to the corresponding slots in said female head.

3. The combination with a male slotter head adapted to be mounted for movement about an axis in cutting, said head having a support for positioning a plurality of male slotter knives, and said knives each having two parallel cutting edges spaced apart, and means for securing said knives on said support in different cutting positions one edge of each knife on the same side of said knives being in a single plane at right angles to said axis, of a female slotter head adapted to be mounted for movement about an axis parallel to said male head axis and in operative relation thereto, the female head having cutting slots of different widths placed end to end and aligned in the direction of their length, each having substantially parallel cutting edges at the opposite sides, the cutting edges on one side of a plurality of said slots being in a single plane at right angles to said axes, both said single planes being on the same side of the knives and slots, respectively and both heads being adjustable in the direction of the axes to bring these planes together.

4. A female slotter head comprising two ring cutter members of substantially the same diameter, one having a peripheral shearing edge in a plane at right angles to the ring axis and the other having two peripheral shearing edges end to end and in different planes at right angles to the axis of the second ring member, a spacer and means for securing said ring members together on opposite sides of said spacer with their axes in alignment, thus assembling the complete head with said edges opposed and spaced apart, forming two slots of different widths.

5. A female slotter head comprising two ring cutter members of substantially the same diameter, one having a peripheral shearing edge in a plane at right angles to the ring axis and the other having two peripheral shearing edges end to end and in different planes at right angles to the axis of the second ring member, a spacer and means for securing said ring members together on opposite sides of said spacer with their axes in alignment, thus assembling the complete head with said edges opposed and spaced apart, forming two slots of different widths, and said rings and spacer having positioning means to give and maintain the same angular relation of the rings and edges whenever they are assembled or reassembled.

6. A female slotter head comprising two knives adapted to be mounted for operative movement about an axis, one having a peripheral cutting edge in a single plane, at right angles to said axis and the other having a peripheral cutting edge ofiset in two planes at right angles to the axis and means for securing said knives together with said edges opposed and spaced apart to form two cutting grooves in substantial alignment and of different widths. v

7. A grooved slotter head having cutting grooves of different widths placed end to end and extending in the same direction, the grooves having cutting edges at each side, the edges on one side of two grooves being in a single cutting plane.

THOMAS S. FITCHETT. 

